1. A Coupled Ice-Ocean Model Based on ROMS/TOMS 2.0 W. Paul Budgell Institute of Marine Research and Bjerknes Centre for Climate Research Bergen, Norway Terrain-Following Model User’s Group Meeting Seattle, August 4-6, 2003 IMR

2. Outline of Talk: Description of ice model Coupling of ice model to ROMS Basin-scale coupled ice-ocean model To do

3. IMR Outline of Talk: Description of ice model Coupling of ice model to ROMS Basin-scale coupled ice-ocean model To do

4. IMR Ice Dynamics Ice dynamics are based upon the elastic-viscous-plastic (EVP) rheology of Hunke and Dukowicz (1997), Hunke (1991) and Hunke and Dukowicz (1992). Under low deformation (rigid behaviour), the singularity is regularized by elastic waves. The response is very similar to viscous-plastic models in typical Arctic pack ice conditions. Numerical behaviour improved significantly by applying linearization of the viscosities at every EVP time step. The EVP model parallelizes very efficiently under both OpenMP And MPI.

5. IMR Ice Thermodynamics Ice thermodynamics are based upon those of Mellor and Kantha (1989) and Häkkinen and Mellor (1992). Main features include: Three-level, single layer ice; single snow layer Molecular sublayer under ice; Prandtl-type ice-ocean boundary layer Surface melt ponds Forcing by short and long-wave radiation, sensible and latent heat flux NCEP fluxes, corrected for model surface temperature and ice concentration, used as forcing

6. IMR Outline of Talk: Description of ice model Coupling of ice model to ROMS Basin-scale coupled ice-ocean model To do

7. IMR Coupling of Ice Model to ROMS Tried to keep things modular: In main3d.F: ice routines NCEP flux routines CALL ice_albedo (ng,tile) CALL cawdir_eval (ng,tile) CALL ncep_flux (ng, tile) CALL ice (ng) CALL ice_frazil(ng,tile)

8. IMR Coupling of Ice Model to ROMS New ice variables stored in mod_ice.F Ice model contained in ice.F: computes ice-ocean fluxes performs EVP dynamics performs advection of all ice/snow prognostic variables performs ice/snow thermodynamics ice_frazil.F: checks for water masses below freezing point computes ice growth mass flux from frazil ice formation adjusts T and S for ice formation

9. IMR Outline of Talk: Description of ice model Coupling of ice model to ROMS Basin-scale coupled ice-ocean model To do

10. IMR Transformed Spherical Grid

11. Surface Temperature (deg C) 1949/03/06

12. Sea Surface Height (m) 1949/03/06

13. Ice Concentration (1949/03/06)

15. Ice Concentration (1949/09/30)

16. IMR Simulated Sea Ice Thickness 1949

17. IMR Simulated Sea Ice Thickness 1949

18. IMR Simulated Sea Ice Thickness 1949

19. IMR Simulated Sea Ice Thickness 1949

20. IMR Simulated Sea Ice Thickness 1949

21. IMR Simulated Sea Ice Thickness 1949

22. IMR Simulated Sea Ice Thickness 1949

23. IMR Simulated Sea Ice Thickness 1949

24. IMR Simulated Sea Ice Thickness 1949

25. IMR Simulated Sea Ice Thickness 1949

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27. IMR Simulated Sea Ice Thickness 1949

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29. IMR Simulated Sea Ice Thickness 1949

30. IMR Simulated Sea Ice Thickness 1949

31. IMR Simulated Sea Ice Thickness 1949

32. IMR Simulated Sea Ice Thickness 1949

33. IMR Simulated Sea Ice Thickness 1949

34. IMR Simulated Sea Ice Thickness 1949

35. IMR Simulated Sea Ice Thickness 1949

36. IMR Simulated Sea Ice Thickness 1949

37. IMR Simulated Sea Ice Thickness 1949

38. IMR Simulated Sea Ice Thickness 1949

39. IMR Simulated Sea Ice Thickness 1949

40. IMR Simulated Sea Ice Thickness 1949

41. IMR Simulated Sea Ice Thickness 1949

42. IMR Simulated Sea Ice Thickness 1949

43. IMR Simulated Sea Ice Thickness 1949

44. IMR Simulated Sea Ice Thickness 1949

45. IMR Simulated Sea Ice Thickness 1949

46. IMR Simulated Sea Ice Thickness 1949

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48. IMR Simulated Sea Ice Thickness 1949

49. IMR Simulated Sea Ice Thickness 1949

50. IMR Simulated Sea Ice Thickness 1949

51. IMR Simulated Sea Ice Thickness 1949

52. IMR Simulated Sea Ice Thickness 1949

53. IMR Simulated Sea Ice Thickness 1949

54. IMR Simulated Sea Ice Thickness 1949

55. IMR Simulated Sea Ice Thickness 1949

56. IMR Simulated Sea Ice Thickness 1949

57. IMR Simulated Sea Ice Thickness 1949

58. IMR Simulated Sea Ice Thickness 1949

59. IMR Simulated Sea Ice Thickness 1949

60. IMR Simulated Sea Ice Thickness 1949

61. IMR Simulated Sea Ice Thickness 1949

62. IMR Simulated Sea Ice Thickness 1949

63. IMR Outline of Talk: Description of ice model Coupling of ice model to ROMS Basin-scale coupled ice-ocean model To do

64. IMR Work in Progress Clean up the code Fix small parallelization inconsistency Developed idealized test cases for analytical.F ICE_BASIN ICE_OCEAN_1D Modify bulk_flux.F to take ice forcing Implement open BC FRS scheme for ice variables (B. Ådlandsvik)

65. IMR Work in Progress/Future Work Implementation on a 4-km grid for the Barents region Run AOMIP Implement full metric terms for curvilinear grid (Hunke and Dukowicz, 2002) Multiple ice thickness categories, energy conservation (NCAR, CICE, Bitz and Lipscomb (1999)) Couple high-resolution ice-ocean ROMS to mesoscale atmospheric model MM5 (Polar)